Question

Tính:

\(\dfrac{2}{5}+\dfrac{1}{5}\)                        \(\dfrac{2}{3}+\dfrac{5}{3}\)                        \(\dfrac{3}{8}+\dfrac{4}{8}\)

\(\dfrac{6}{9}+\dfrac{2}{9}\)                         \(\dfrac{12}{18}+\dfrac{7}{18}\)                    \(\dfrac{7}{4}+\dfrac{2}{4}\)

Answer 1

\(\dfrac{2}{5}+\dfrac{1}{5}=\dfrac{2+1}{5}=\dfrac{3}{5}\)

\(\dfrac{2}{3}+\dfrac{5}{3}=\dfrac{2+5}{3}=\dfrac{7}{3}\)

\(\dfrac{3}{8}+\dfrac{4}{8}=\dfrac{3+4}{8}=\dfrac{7}{8}\)

\(\dfrac{6}{9}+\dfrac{2}{9}=\dfrac{6+2}{9}=\dfrac{8}{9}\)

\(\dfrac{12}{18}+\dfrac{7}{18}=\dfrac{12+7}{18}=\dfrac{19}{18}\)

\(\dfrac{7}{4}+\dfrac{2}{4}=\dfrac{7+2}{4}=\dfrac{9}{4}\)